The Past, Present and Future in Tube- and Paper-Based Colorimetric Gas Detectors

Colorimetric gas detectors have been widely applied in many fields such as environmental sciences, industrial hygiene, process control, forensic science and indoor air quality monitoring. They a history of about 100 years include devices detector tubes paper-based detectors. The sensitivity selectivity the colorimetric are relatively high compared to other types semiconductor, catalytic combustion electrochemical Detection concentration can be performed by naked eye some These methods do not require an electrical power source simple, so they suitable for field operations. This review introduces provides general overview development research Recently, improved. New materials enzymes or particles with large surface area utilized improve sensitivity. Moreover, new without toxic developed reduce load. At present, there is rapid IoT sensors fields, which might extend applications near future.